Bridging for floor joists and the like



June 1, 1948. P. A. GSTALDER BRIDGING FOR FLOOR JOISTS AND THE LIKE Filed June 19, 1946 INVENTO R. 1:12P

ATTORNEYS.

Patented June 1, 1948 BRIDGING FOR FLOOR JOISTS ANDTHE LIKE Paul A. Gstalder, Gibsonia, Pa. Application June 19, 1946, Serial No. 677,767

2 Claims.

This invention relates to improvements in bridging for floor joists and the like, and more particularly to reinforced straps adaptable for different sized joists which can be secured to the joists more firmly, with greater ease and a corresponding savlng of time.

An object of the invention is to provide a steel floor joist bridging element bent into a reinforcing V formation and so formed as to be applicable with the equal facilities to different sized joists, for example, six, eight orten inch joists, on sixteen inch centers; providing the bridging element with notches in the lateral edges of its V sides and intermediate corresponding nail holes for the diiferent sizes of J'oists whereby when the bridging element is placed in position the extending portion of the V formation may be flattended against the edge of the joist and be secured thereto with equal facility for any of said standard sizes of joists.

Another object of the invention is to provide a double length joist bridging element of the type above set forth and wherein the intermediate portion of the bridging strap element is provided with struck out flaring prongs for securing it to the edge of the intermediate floor joist struck out prongs are adapted to be embedded in edge of the joist at outwardly flaring angles with respect to each other when driven into place with the upper strap portion, preferably in a countersunk position with the upper surface of the bridge strap flush with the normal upper edge surface of the joist. The prongs so embedded are more positive in their securing action against movement or removal of the strap from such countersunk position. This securing of the strap is positive even before the free ends of the bridging element are secured to the next adjacent joists on the opposite sides.

Another object of the invention is to provide a metal floor bridging element which is generally of relatively flat, strap-like formation, to facilitate packing, storing and handling by workmen, but which bridgin element may be readily bent at its minor or anchoring end portion, firstly, so that said end portion is in obtuse angular relation to the main diagonal portion of the element and in face-to-face contact with the lower side of the joist to which it is anchored, and secondly, so that its terminal portion is in right angular relation to the obtuse angularly related portion and in face-to-face contact with the vertical side of the joist; the minor or anchoring end portion being provided with prongs struck out from the bridging stock in a manner to firmly bite into the wooden joist, and to guard against the prongs being flattened instead of penetrating the wood joist.

Further objects, details and advantages of mv improved floor joist bridging element will appear in the following specification and as illustrated in the accompanying drawings forming a part thereof.

In the drawings:

Fig. 1 is a longitudinal plan view of a floor joist bridging element in accordance with my invention Fig. 2 is a side elevation of the same.

Fig. 3 is an enlarged cross-section thereof taken substantially on line 3-3 of Fig. 2.

Fig. 4 is a fragmentary vertical sectional view taken longitudinally of a bridging element illustrating the manner 0f application of the bridging element to floor joists of different sizes, and

Fig. 5 is an enlarged cross-section on substantially the line 5-5 of Fig. 1.

Referring to the drawings, Figures 1 and 2 illustrate a bridging element for bridging three floor joists comprising a steel strap ll] of such a length to bridge different sized joists spaced at standard distances, for example six, eight or ten inch joists on sixteen inch centers. Though larger joists would mean a corresponding extension of the length, strap I0 is illustrated of a length suitable for joists up to ten inch. Strap I6 is fiat at its mid-portion and is provided with a pair of downwardly struck outwardly divergent prongs ll beyond which the strap is V-shaped at l2 and I3 so bent to provide reinforcing for its maximum length between two ten inch joists with its ends flat and provided each with a pair of upwardly struck prongs l4 and I5. Strap I0 is provided with nail holes l6 adjacent its ends for additional secu'ring means if desired. Definitely spaced nail holes l1, l8 and I9 inwardly from the ends and prongs I4 and iii are provided corresponding respectively with bridging lengths for ten, eight and six inch joists and the strap is notched in its opposite edges at 20, 2| and 22 at the exact corresponding distances of nail holes 11, I8 and I9.

In applying my improved bridging strap to floor joists reference is made to Fig. 4 wherein two six inch joists are shown; six inch joist 23 to which the intermediate portion of the strap is secured, and six inch joist 24 to which an end of the strap is secured are shown in solid lines while 23, 23", 24 and, 24 are dotted to represent eight and ten inch joists, respectively.

The intermediate portion of the strap is secured to joist 23 (23 or 23") by driving prongs l I thereinto crushing the wood of the upper edge surface .of the joist to countersink the strap until it is 'flush therewith so as not to interfere with flooring when it is laid. The outwardly divergent prongs enter the wood in a divergent manner and thus secure the strap in its countersunk position.

It will be noted that the reinforcing V format--- is extensive substantially tion of the strap l throughout its length for any of the sizes of joists with which it is employed, this beingarranged for by the nail holes l1, l8, l9 and corresponding notches 20, '21 and 22 employed in connection with joists of the different sizes.

In applyingthe end of strap In to the larger size joist 24" a nail 25 is driven through the corresponding (outer) nail hole [1 into the corner of-'the joist, with which it corresponds; the projecting end'is bent as provided for by notches 20 'and driven upwardly, prong l entering the edge -surface of the joist, and, the further extension of the end is bent upwardly and prong l4 driven into-the opposite side surface of the joist. A nail may be driven through nail hole It, if desired.

In applying the end to smaller joists 24 or 24' a nail 26 or 2'! is driven through the corresponding nail hole E9 or 18 respectively into the corner of the joist. Then by pounding (bending) the extending end of strap I'll against the under edge of the joist, as provided for by the corresponding notches 22 or 2|, respectively the V portion of the strap is flattened against said edge of the joist and the adjacent portion is reshaped corresponding in each instance the same aszfor: the larger size joist. The connection is completed by driving the extending portion of the ends upwardly with prongs l4 and I5 penetrating the side surfaces of the joists in positions corresponding with the joist size.

It lWiH be noted that the holes l1, l8 and I9 arenot uniformly spaced apart, but rather that the: spacing between the centers of holes l8 and his less than the spacing between the centers of holes. I! and 13. In determining this spacing of the holes with respect to one another and with-respect to the transverse center of the bridging one'may figure that a standard joist of two inch thickness is in reality dressed to a thickness of: /8 inches. Since the transverse center of the bridging is centered above the joist 23, 23 or.23" as the case may be, it is determined that approximately /16 of an inch of the bridging will rest upon the said joist to either side of its center. If the joists are on sixteen inch centers, the hypotenuse of an imaginary right angle triangle, the short leg of which corresponds to the depth of joist 2 5 (dressed to a depth of 5 /8 inches) and the longer leg of which corresponds to the space between the joists 23 and 24 (approximate- 1y 14%; inches) will be approximately 15% inches, such determines the location of the center'of perforation 19, or in other words, 16 /16 4 inches from the transverse center of the bridging. Likewise the hypotenuse of such a triangle for an eight inch joist (dressed to approximately 7 inches in depth) will be found to be 16 /4 5 inches, thus making the perforation I8 centered /2 of an inch from the center of perforation l9. And, as to adapting the bridging for a ten inch joist (dressed to approximately 9 inches in depth) the hypotenuse of the imaginary triangle 1 will be 17 /4 inches, thus making the perforation l'6 centered one inch from the center of perforation [8.

The prongs I4 and I5 are preferably struck out of the body portion of the bridging in a manner 5 that they are normally inclined toward the transverse center of the strap It] as shown in Figs. 2 and 5, instead of extending outwardly at right angles to the plane of the strap, as is common in the. art of box straps and in the art of bridging, -asshown in Patent 1,649,226 issued Nov. 15, 1927 granted on an application filed by me Dec. 2, 1925. The purpose in so doing is to guard against flattening of the prongs when installing the bridging and to render the bridging more efficient. For instance the end portions of the strap of the bridging is bent during installation, as shown in Fig.4, and this is usually done by hammering the body portion, using the joists as an abutment-in somewhat the same manner that the square faced end of an anvil is used when bending metal. As the portion of the bridging strap equipped with the prong to be driven into the joist, approaches the latter, during the bending operation, the prong is likely to be flattened or bent back upon the bridging stock and its juncture with the latter is likely to be broken if the prong extends with its axis at a right angle to the plane of the stock, or is inclined away from the transverse center of the bridging strap. By disposing the 40 prongs l4 and [5 with their axes inclined toward the transverse center, the prongs more nearly approach the face of the joist into which they are to be driven, at right angles to the face of the joist, than if the prongs stand at right angles to the plane of the bridging strap. This inclination may be 1 or more from the plane of the bridging stock.

While above dimensions are accurate for dressed joists in actual practice it is found that 5 they are also applicable -to joists in the rough,

based on the same spacing between centerssixteen inch centers. This is due to the corresponding increases in thickness of the joists and other factors as will be apparent. In practice also the application of these straps will also correct inaccuracies in the joists themselves when they are off center, warped or otherwise distorted, being constructed to dimensions based upon accurate computations, the application of such brac- 0 ing corrects such defects as referred to, thereby providing a better floor foundation.

Having set forth in detail a highly satisfactory embodiment of a bridging strap for floor joists it will be seen that such construction is obviously subject to variations within the scape of my invention which is claimed as follows.

I claim:

'1. A bridging member for bracing parallel joists, comprising a longitudinal strap member V-shapod in cross section having a flat portion at one end thereof provided with a plurality of divergent struck-out prongs extending therefrom, a flat portion thereof at the other end provided with securing means, and the V-shaped portion adiacent the last mentioned flat portion provided with spaced notches in its lateral edges and nail holes intermediate and in alignment with the notches.

PAUL A. GSTALDER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 10 Number Name Date 1,523,711 Powell Jan. 20, 1925 1,649,226 Gstalder Nov. 15, 1927 1,656,741 Lane Jan. 17, 1928 

